AerSimulator.coupling_map is not properly generated

[t-imamichi]

Informations

• Qiskit Aer version: 0.13.0
• Python version: 3.10.13
• Operating system: macOS 14.1

What is the current behavior?

AerSimulator becomes BackendV2 but AerSimulator.coupling_map does not seem properly generated.

Steps to reproduce the problem

from qiskit_aer import AerSimulator

backend = AerSimulator(coupling_map=[[0,1]])
print('backend.coupling_map:', backend.coupling_map, type(backend.coupling_map))
print('backend.configuration().coupling_map:', backend.configuration().coupling_map)

output

backend.coupling_map: None <class 'NoneType'>  # expected `CouplingMap`
backend.configuration().coupling_map: [[0, 1]]

What is the expected behavior?

AerSimulator.coupling_map returns the coupling_map instead of None.

Suggested solutions

AerSimulator.set_options allows users modify coupling map on-demand. It might be good to overload BackendV2.coupling_map to generate a coupling map dynamically.